Evening star. [volume] (Washington, D.C.) 1854-1972, 1887-06-18
I'm Behalf Of Tree-Spraying.
To the Editor of the EVENING STAR:

As you have ever been ready to champion the
cause Of tree protection in our city, venture to
orfer the following suggestions ON the subject Of
spraying trees with London purple. The only
argument OF any force against the plan proposed
by Prof Riley is its supposed danger, while its
cheapness efficiency and neatness are beyond dis
pute. Ir, therefore, the following facts prove as
conclusive TO other minds as TO my own, we may
regard the spray as boon to the city. All medical
works place the minimum fatal dose Of arseniouS
acid at about grains. Tard1en places It at 1.54
grains 10 PSI grains, and names .154 grain as the
smallest amount capable under any circumstances
OF causing any serious SUMMONS. these To,ureS
applying 10 fnvalids, weak children, &C. London
purple contains 20 percent OF arsenious acid the
sOutiOnused Is pound TO 100 gallons 800 pounds,
OF water, and as this makes the proportions i
grain aIsenious acid TO z, 600 grains OF water 1t
Will be seen that nearly an ounce of the solution
must be ingested 10 cause serious symptoms
while the smallest amount that could cause fatal
poisoning Is two-thirds OF a pint. A teaspoonful
against malaria Vow, considering the fact
that one gallon OF this mixture applied
that the leaves are simply aER Sv ns
spray, that there Is no drip from the trees and
that they would dry in a short time leaving the
possible that any child could catch, In his mouth
even, the quantity required for the production OF
he would have 10 lick or chew 5000 OF the leaves
IN order 10 get .154 gr, where the 80 grains con-
tanned In gallon OF the solution has been distnb-
uted over the million leaves OF large tree: and 1t
Is selfevident that the drip from the tree AFTER
rain, would be so much more dilute than the orig
tnal solution that doubt If any stomach could
hold enough TO cause trouble, even II the mouth
were OF sufficient TO catch rain-drOps by the
barrel full IL may be doubted by some whether
such weak solution In such small quantity would
prove efficient; but fortunately, this question has
been settled by practical tests. As TO the sparrow
should the spray be used-Inay the Lord in His
mercy have made him extremely susceptible TO
arsenic Very respectfully, W. p. CARR.
The Mount Pleasant Sewerage.
To the Editor Of THE EVENING STAR:
read with much surprise the plan of sewerage
devised for Mount Pleasant by the military eng1-
neer, a published IN TEE STAR Of the 18th and
especially the statement that it was designed "w1th
the view OF following the natural drainage so Tar
as possible" Now, as everybody knows Mount
Pleasant Is upon the hill bordering on the Rock
Creek Valley, and the natural drainage would
seem 10 be down that valley; but instead OF TAX
ing the sewerage that way this plan PROPOSES 10
carry IL eastward TO sth street and connect with
the Boundary sewer, which empties into the East
ern Branch a short distance below the Benning's
Bridge road, distance OF two or three miles from
where the sewage Is created. The result of course
WIN oe. that The sewage from Mount Pleasant and
all that region will be dumped out on the fats at
the west side OF the Eastern Branch at IsherwoOd
and from there all the way down TO Giesboro Point
Will be spread out over the flats so that In a Few
years the hats there will be great a nuisance as
were the natS above and around the Long BRIDGE
and which necessitated the expenditure OF the
vast sums now being used TO reclaim them
Another remarkable feature OF this plan Is that
/, Will necessltate the use or pump with large
annual, will as original, expenditure TO run
It and keep 1t in order. The idea OF using a
pump for the sewerage OF a place on the top OF a
hill $50 feet high, with natural-drainage valleys
dyergng IN all directions toward the valley below
Il one that could never have occurred to the
mlnd OF anyb body but military engineer.
The point TO which most strenuously object Is
making the rats OF the Eastern Branch the dump
Ing ground for al the sewerage OF the entire
northwestern portion OF the District outside Of
Boundary street. EAST WASHINGTON.
June Id, lSS7.